Apparatus for producing sound



July 14, 1931 E. c. GUEDGN APPARATUS FOR PRODUCING SOUND Filed March 14, 1929 W O t n e V n I Emile C. Guecion,

HIS Attorneg.

1 construction in which a coil spool Patented July 14, 1931 EMILE C. GUEDON, OF SCHENECTADY, NEW YORK, ASSIGNGR T0 GENERAL ELECTRIC COMPANY, A. CORPORATIGN OF NEW YGRK- APPRRATUS FQR PRODUCING EiDUND Application filed March 14, 1222.. Serial lilo. M71060.

My invention relates to apparatus for producing sound and has for its principal object the provision of an improved sound producing apparatus which is simple and rugged in construction and may be readily operated to convert electrical impulses into sound or vice versa.

In the manufacture of sound producing devices, such as loud speakers for example, it is desirable to simplify the parts so as to facilitate mass production and at the same time to maintain or increase the efiiciency of the loud speaker. In accordance with my invention the efiiciency of the magnetic type of loud speaker is increased and mass production thereof facilitated by an improved of a resilient metal is provided within which the vibrating a rmature is fastened to projections from the walls of the spool, which provide the restoring or centering force as well as the fulcrum for the armature.

My invention will be better understood from'the following description when considered in connection with the accompanying drawings and its scope will be pointed out in the appended claims.

Referring to the drawings Fig. 1 illustrates a cross section assembly view of aloud speaker built in accordance with my invention Figs. 2 and 3 illustrate details thereof, and liigs. 4 and 5 illustrate a modification of the invention.

The sound producing device illustrated in Fig. 1 includes a cone 10 which is driven through a driving rod 11 by an armature 12. The armature 12 is supported by projections 13 and 14 from the walls of a coil spool composed of members 15 and 16 which are prelerably made of some resilient non-magnetic and high resistance meta A coil 17 adapted to receive or generate speech current surrounds the spool, and a permanent magnet 18 provided with pole pieces 19; 20, 21 and 22 produces a magnetic field in which the armature moves.

Fig. 2 illustrates an assembly of the spool and pole pieces illustrated in Fig. 1; and Fig. 3 is an exploded view thereof. The members 15 and 16 are provided with upwardly armature.

and downwardly extending lugs which are bent into locking position when the members are assembled and which interlock them with each other and with end plates 23 and 24. Space is provided for the pole pieces between the end plates and the spool parts in which the pole pieces are held in place .by screws 25. It may be noted in this view that armature 12 is one continuous piece of metal having no grooves cut therein to afiect its magneticreluctance and no separate member is required to support and center it, the lugs 13 and 14 being simply a part of the spool metal.

A. modification of my invention is illustrated in Figs. d and 5." In this construction the spool consists of one piece of metal 26 which is provided with flanges 27 and 28 for supporting the pole pieces and a projecting portion 29 to which the armature 12 is fastened. In this modification the projecting portion 29 again provides the restoring force as well as constituting the fulcrum for the This construction is somewhat more simple than the structure illustrated in Figs. 1 to 3.

Sound producing devices built in accord ance with my invention. have the advantage that the problem of mounting and centering the armature is greatly simplified and the armature is made of a rectangular piece of metal which possesses low magnetic reluctance and tends to increase the operating efficiency of the device.

What I claim as new and desire to secure by Letters Patent of the United States is l. in a sound producing apparatus, a coil spool havin a wall provided with an inwardly promoting flexible portion formed from said wall and an armature arranged to move within said spool and rigidly attached to said portion.

2. lln a sound producing a para-tus, a coil spool provided with a pair oi opposing projecting portions, and an armature arranged to move within said spool and rigidly attached to said portions.

3. in a sound producing device, a hollow sheet metal spool rovided with an inwardly projecting portion, an armature arranged to move within said spool and rigidly at- Mid whooihod intermediate its ends to said inwardly projoo oing portion" integral cod spool molndm a boilloW porfmon- F orovlded wlth on mwar 1y ord jocting suppom, ond flanges Poem; at an. angle "with said porciom to form the ondsof said spool. 5. A speech current device including an intogml ooid spool inoludin a hollow body portion, projection wit in said pomiom flanges wronged to form the ends of soifi spooi, and wmotmo moumzed on said projootion and omondiog through said body pox ibiomu 30 In oooosfio device, a movable armoomro ooii spoofl provided with flanges and with on imwoodly poojecting portion adopted to soppowb armature, and magnetic members to cooperate with said ormoisme and monmtod on said flanges,

In Witness Whomof, I have hereunto 59% my hood this 136m day of March, 1929.

Q Y a o-moo: 

